Endoscopic procedures to treat abnormal pathologies of the gastro-intestinal (“GI”) canal system, of the biliary tree, of the vascular system and of various other body lumens are becoming increasingly common. The endoscope is basically a hollow tube that is placed at a desired location within the body to facilitate access to the relevant body ducts and lumens, etc. The endoscope itself cannot carry out many of the required procedures. To that end, the endoscope is fitted with a lumen, or internal channel, which permits the user to insert various medical devices therethrough to the location that requires treatment. Once the distal end of the inserted device has reached the tissue to be treated, it can be manipulated using controls which remain outside the body.
An hemostatic clipping tool is one of the devices which may be inserted through an endoscope so that treatment may be carried out. Hemostatic clips are deployed from the clipping tool and are used to stop internal bleeding by clamping together the edges of a wound. The clipping tool complete with clips attached to its distal end is inserted through the endoscope to the location of the bleeding. A clip is then remotely manipulated into position over the site of bleeding, clamped over the wound and detached from the tool. After a number of clips sufficient to stop the bleeding has been deployed, the tool is withdrawn from the patient's body through the endoscope. The size and shape of the clips and of the clipping tool are limited by the inner diameter of the endoscope's lumen, thus placing constraints on the design of the clip positioning and release mechanisms.
One challenge facing the endoscope operator is to properly position the hemostatic clips over the wound, so that closing the clips over the tissue will be effective in stopping the bleeding. If a clip is deployed improperly, additional clips may be required to stop the bleeding extending the time required for and the complexity of the procedure and leaving additional medical devices within the patient. It is also important for the device operator to be certain of the status of the clip during the deployment operation. For example, before withdrawing the tool from the endoscope, the operator should have positive indication that a clip has fully deployed, and has been released from the tool. At the same time the design of the tool should ensure that clips are fully released after they have been closed over the tissue.